JPS6244389B2 - - Google Patents

Description

BACKGROUND OF THE INVENTION The present invention relates generally to wire clamp assemblies for electrical terminals, and more particularly to wire clamp assemblies for engaging a wire with a generally planar terminal member surface of a terminal block or the like. Associated with screw and washer wire clamp assemblies for holding in relationship.

Screw and washer clamp assemblies are known in the art that include a screw threadably engaging a terminal member having internal threads and a clamp washer advanced by the screw to clamp a wire to the terminal member surface. There is. For example, this type of arrangement is disclosed in US Pat. Nos. 3,177,456 and 3,816,820. However, many of the clamp washers devised heretofore allow some lateral or axial movement or twisting of the wire even after clamping, which results in mechanical or electrical failure of the connection. Other clamp members provide a secure connection only if great care and effort are taken while positioning the wire and advancing the screw and washer members for connection. Additionally, many clamping members are designed to connect only a limited size range of wires, and furthermore, many connectors are only functional when connecting two wires of different sizes to the same terminal. It becomes impossible.
Thus, many conventional clamping devices require considerable time and effort to establish a mechanically and electrically acceptable connection, as well as selecting the appropriate device for the wire size to be connected. It is not fully satisfactory in its use, as errors in doing so are quite possible.
In an attempt to alleviate some of these problems, the various clamp washers designed for use in this type of assembly are relatively complex in shape and therefore difficult to manufacture and It's expensive.
Therefore, there has been a need for a more reliable, more flexible, and less expensive terminal washer, which we believe is satisfied by the present invention.

OBJECTS AND SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a new and improved screw and washer type wire clamp assembly which provides a screw and washer type of wire clamp assembly that is capable of connecting wires and terminals. applied to make simple but reliable mechanical and electrical connections.

Another object of the invention is to provide a wire clamp assembly of the type described above, which is adapted to provide satisfactory mechanical and electrical connections over a considerable range of wire sizes. .

Yet another object of the invention is a wire clamp assembly of the type described above, adapted to establish a satisfactory mechanical and electrical connection for connecting two different size wires to the same terminal. The goal is to provide the following.

Yet another object of the present invention is to provide a wire clamp assembly of the type described above which is relatively simple to incorporate into a terminal member and which is also relatively simple and inexpensive to manufacture.

The object of the present invention is also common to the object of the prior art in that it provides a terminal fastener for achieving electrical connection with a lead wire (wire). However, the present invention achieves the same objectives as those of the prior art described above in an improved manner.

In summary and in accordance with the foregoing objectives, a wire clamp assembly for use with an internally threaded terminal member having a flat conductor surface has an external thread for engaging the internal thread of the terminal member. a screwdriver head, and an unthreaded shank portion intermediate the screwdriver head and the externally threaded portion. A plate-like washer member is preferably mounted in captive relation on the unthreaded shank portion and is capable of engaging the fastener head for movement toward the terminal member surface to clamp the at least one wire. . The washer member has a lower surface facing the flat terminal member surface, the lower surface includes at least one ramp defined by an end surface that extends radially outwardly from the screw member, and slanting downward toward the terminal member to increase the effective thickness in this direction;
The ramp is spaced apart from the screw member at its inner end and approximately parallel to the outer periphery of the washer member at its outer end.

In a preferred embodiment, the washer member is generally square and its lower surface is provided with two pairs of opposed lamps of the type described above, arranged substantially symmetrically with respect to the sides of the square washer member. When the screw and washer member move toward the terminal, they force the wire inward so that a pair of opposed lamps engage to clamp the pair of wires at opposite lines of the screw, and the other opposite pair of sides of the lamps are attached to the inner side of the wire. It roughly defines the limits of movement. Additionally, in a preferred embodiment, the lower surface of the washer spans generally laterally to the wire for biting engagement with the wire when the screw and washer member are sufficiently advanced relative to the terminal member. , with downwardly curved corners forming a pair of downwardly sloping edges.

Other objects, features and advantages of the invention will be understood from the following detailed description of the illustrative embodiments, taken in conjunction with the accompanying drawings, in which like reference numerals indicate like elements and parts.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring initially to FIGS. 1 and 2, a conventional support or terminal block or member 10 is shown.
As shown in the example, this conventional type has a substantially flat plate-like conductor surface 1.
2 and internal threads 14 for receiving a wire clamp or terminal assembly, generally designated 16, constructed in accordance with the present invention. A pair of wires 18 that are to be mechanically and electrically connected to the terminal member 10
and 20 are also illustrated. For purposes of illustrating the flexibility of the present invention in accommodating different sizes or types of wire, wire 18 is shown as a solid wire, and wire 20 is shown as wire 1.
It is shown as a strand of size or diameter somewhat larger than 8. However, the wire clamp assembly 16 of the present invention is suitable for use over a wide range of wire diameters or sizes, and is suitable for use with both solid and stranded wire, and is suitable for use with wire 18. 20 is shown by way of example only.

The wire clamp or terminal assembly 16 includes a head or driver portion 24, an externally threaded shank portion 26 for engagement with the screw 14 of the terminal block member 10, and an intermediate portion between the head 24 and the threaded portion 26. The screw member 22 (screw tightening member 22) is provided with a shank portion 28 without a screw. A clamping member 30 in the form of a washer-like member with a central hole 32 is attached to the fastener 22.
(screw tightening member 22),
It is then held captive onto an unthreaded shank 28, preferably by a screw on the shank 26. For example, the screw member 22 is formed from screw stock in a conventional manner, the threaded shank 26 is formed by rolling, and the larger diameter of the thread is larger than the diameter of the unthreaded shank 28. A washer member 30 is also disposed on the unthreaded shank portion 28 such that the washer member 30 is also larger than the central hole of the washer or clamp member 30. Thus, the clamping member or washer 30 is held in captive relationship on the fastener 22 after the threaded portion 26 is formed.

As best shown in FIG. 2, the length of unthreaded shank 28 and the diameter of central hole 32 are:
This is such as to allow some freedom of movement of the washer or clamp member with respect to the unthreaded shank portion 28 of the screw member 22. When the fastener 22 is withdrawn from the terminal 12, the washer is lifted and the wires 18 and 20 can be positioned for clamping with a little free movement allowed to the washer.

In the illustrated embodiment, the washer or clamp member 30 is generally square and includes a lower surface 33 that faces the terminal member 10 when the clamp assembly is connected to the terminal member. two pairs of opposing lamps or inclined surfaces 34,36 and 38,4;
0 is rigidly formed integrally with the surface of the clamp member 30 by deforming the main body of the member 30.
These lamps are arranged approximately symmetrically near the center of the sides of member 30. these lamps 3
4, 36, 38 and 40 are generally trapezoidal and slope outwardly towards the periphery of the washer and slope downwardly increasing in height.

This lamp 34 will be described in detail below, but it will be appreciated that the remaining lamps 36, 38 and 40 are of the same configuration.

Referring to FIGS. 4-6, the ramp 34 is generally rounded outwardly and has a downwardly sloped surface 42 that is generally flat and flat at the outer periphery of the washer 30. terminating in a surface 44, thus providing a lamp with an outwardly increasing height. The lamp 34 is generally trapezoidal, defined by an interior end 43, a pair of outwardly flared generally planar side ends 45, and a peripheral end 47 of the member 30. The sloping surface 42 begins laterally from the central hole 32 at an outwardly spaced end 43 such that the narrow base of the trapezoidal shape formed by the ramp 34 is centered It is spaced apart from the hole and its wide base is generally parallel to it below the outer periphery of the washer.

With reference to FIGS. 5 to 7, the clamp member 30
Noting angles 46, 48, 50 and 52, we get
Corners 46, 48, 50 and 5 as shown
2 is deflected inward or bent. Each corner thus provides a pair of edges 54 and 56;
These bite into the clamped wires to prevent the wires from being pulled out, as will be described in detail later.

The operation of assembly 16 in clamping wire members 18 and 20 will now be considered. In this connection, the fastener 22 is withdrawn from the hole 14 in the block 12. Clamp member 3 attached to the screw member in a captive manner
0 is raised relative to surface 10, thus facilitating initial positioning of wires 18 and 20. Once these wires are positioned, the fasteners are screwed inward. Referring to Figure 2,
Fastener 22 advances sloped surfaces 42 of ramps 34 and 36 into engagement with wires 18 and 20. Most importantly, as the washer 30 advances relative to the terminal member 10, the sloped surface 42
forces wires 18 and 20 inwardly toward central hole 32. Conveniently, the flat surface 44
wire 18 by and rounded inclined surface 42
and 20 to provide a secure engagement to the wire, substantially preventing excessive cutting or damage to the wire. Another important point is that this inward movement of wires 18 and 20, driven by ramp 34,
This wire engages the side ends 45 of the opposing pair of ramps 38 and 40, thus defining the limits of inward movement and allowing the threaded portion 26 of the fastener to damage the wire. prevent excessive engagement.

As shown in FIG. 2, when the surface 42 of the ramp 34 is fully advanced, the wires 18 and 20
engages the surface of, i.e. causes a slight deformation,
Thus, the wire 20 is firmly engaged between the clamping member or washer 30 and the terminal member 10.
hold. Advantageously, the described lamp configuration is suitable for similar engagement and inward force on both solid and stranded wire over a considerable range of sizes or diameters. In this regard,
The circular continuous slope of the lamp surface 42 and its trapezoidal slope are important features of the invention.

Turning attention to FIGS. 5-7, corners 46, 4 of the generally square washer or clamp member 30 are shown.
8, 50 and 52 in clamping will now be considered. These corners are located at a distance slightly above the plane of the lamp 44 and are located at a constant distance from the edges 54 of the corners.
or the lamp 3 before 56 engages the wire.
4 first engages the wire and performs the internal movement described above. When wire 18 or 20 is clamped, edges 54 and 56 of corners 48 and 52 dig into the surface of wire 18.

A three point grip engagement is thus formed along each of the wires 18 and 20 by the edges and ramps of the clamping member or washer 30. Then, the lamps 34 to 40 and the downwardly bent corner 4
In cooperation with wires 6-52, wires 18 and 20 are aligned generally parallel to each other on opposite sides of screw member 22. Advantageously, this symmetrical arrangement of ramps and corners facilitates desired alignment of wires 18 and 20 and consequent grip engagement.
Furthermore, this symmetrical arrangement ensures that similar engagement and clamping of the wire by washer 30, for example, at ramps 38 and 4, will occur when the wire is oriented 90 degrees rotated from the illustrated position.
0 is caused by engagement with the wire. Additionally, the three areas of interlocking engagement effectively
and 20 in any direction, and advantageously provides an unexpectedly large amount of resistance against any force attempting to pull the wires 18 and 20 out of the wire clamp assembly once engaged therein. Provide quality.

Referring again to FIGS. 1 and 2, lamp 34
40 and downwardly curved edges 46 to 52.
may be simply and inexpensively formed into the clamp member or washer 30 by conventional stamping operations. Furthermore, it will be appreciated that this formation of the ramp and edge imparts a complementary shape to the surface 58 of the washer facing the head or driver portion 24 of the screw member 22. In particular, for lamps 34-40, surface 58 has complementary configurations of depressions or valleys 34a, 36a, 38.
a and form 40a. As best shown in the partial cutaway view of FIG. 2, the valleys 34a and 36a extend substantially as far as the symmetrical ramps with respect to the outer periphery of the head or driver portion 24 of the screw member 22. It's going inside. Accordingly, the engagement or support surface formed between the head 24 of the screw member 22 and the surface 58 of the washer 30 is substantially separated from the ramps 34-40 as indicated generally by arrow 60. radially inward. That's why the second
With respect to the screw member 22, as best shown in the figures, the screw head 24 is located at the arrow 60.
At this point, there is a tendency to compress the washer 30 approximately radially inward from the point of engagement of the wires 18 and 20 of the clamp member 16. Thus, the larger wire 20 to engage the smaller wire.
causes the washer or clamp member 30 to assume a somewhat inclined position with respect to the axis of the screw member 22.

As mentioned above, the diameter of the central hole 32 in the washer 30 is sufficiently large with respect to the shank of the screw 22 to permit the relative movement required to accomplish this tilting action. The contact of the screw head 24 on the washer 30 is approximately radially inward of the engagement of the washer 30 with the wire 20, so that the wire 20 cannot act as a fulcrum and tilt in the opposite direction. I understand. Therefore, on the opposite side of the washer, ie the clamping member 30, the corner 4
8, 52 and ramp 36 achieve the same engagement of large wire 20 with a small wire, such as wire 18. There is of course no tilting of this kind when two wires of equal diameter are engaged, and the opposing ramps engage and clamp the two wires simultaneously.

The foregoing has been applied to position and clamp either a single wire or a pair of substantially parallel aligned wires in order to make a sufficient mechanical and electrical connection with a terminal member. This is a wire clamp assembly. The illustrated and described clamping member or washer further provides a three-point engagement with the wire being thus clamped to substantially prevent movement of the wire in any direction once clamped. Especially 3
Such engagement at a point provides an assembly that significantly resists pull-out of the wire once engaged therein. The described wire clamp assembly may further be applied to engage pairs of wires of different diameters or relative sizes, whether solid or stranded, and over a wide range of wire diameters. There is.

Both the present invention and the prior art accomplish the basic purpose of clamping lead wires. However, the present invention does so in a more reliable and more productive manner. In this regard, the angled ramps 34, 36, 38, 40 urge the wires inwardly. And the downwardly curved corners 46, 48, 50, 52 not only cooperate with the lamp in urging the wire inwardly, but also cut into the wire and cause it to "pull out".
out)”. As shown in the drawings, when two lamps facing each other clamp a wire, the adjacent lamps that do not contribute to the clamping action limit the inward movement of the wire. The most important thing is that the dimensions are sized. This prevents the wire from being forced into engagement with relatively sharp screw threads. When the screw member rotates (if the wire engages the thread), the thread can damage the wire due to relative movement between the thread and the wire. Such (wire) damage is clearly prevented by the present invention.

Although preferred embodiments have been illustrated and described herein, the invention is not limited thereto. To the contrary, modifications and variations may be envisioned by those skilled in the art and are to be understood as forming part of the invention insofar as such modifications are within the spirit and scope of the claims. .

[Brief explanation of the drawing]

1 is a side view of a wire clamp assembly according to the invention in conjunction with a pair of wires and a portion of a terminal member; FIG. 2 is the same side view as FIG. 1 but partially cut away; FIG. Figure 3 is a bottom view of the clamp washer portion of the wire clamp assembly of the present invention, and Figure 4 is a line 4--4 in Figure 3. 5 is a cross-sectional view taken in a plane along line 5--5 of FIG. 3; FIG. 6 is a perspective view of a wire clamp assembly according to the present invention; and FIG. 7 is a perspective view similar to FIG. 6 of the wire clamp assembly associated with the wire. 12...Conductor surface, 14...Female thread, 16...
Wire clamp assembly, 18... Wire, 20...
... wire, 10 ... terminal member, 22 ... screw member, 24 ... driver part, 26 ... shank part with male thread, 28 ... shank part without screw,
30... Washer member, 32... Center hole, 34,
36, 38, 40... lamp, 42... downwardly inclined surface, 44... flat surface, 43... internal edge, 45... planar side edge, 47... peripheral edge, 4
6, 48, 50, 52... Corner, 54... Edge, 5
6...Edge, 58...Surface, 34a, 36a, 3
8a, 40a...Tanibe.

Claims (1)

[Scope of Claims] 1. A terminal wire clamp assembly for engaging a terminal member, etc., which in combination includes a screw clamping member and a washer that is captively mounted on the screw clamping member. a clamping member having a shape, the clamping member having a substantially polygonal plate-shaped washer, the plate-shaped washer having a central opening in which the screw fastening member is engaged. the screw clamping member is used to bias the washer toward the terminal member to clamp the wire thereto, and the corners of the washer are bent downwardly toward the terminal member. In a terminal wire clamp assembly in which the lower surface 33 of the washer member 30 extends toward the terminal member 12, the lower surface 33 of the washer member 30 extends toward the terminal member 12. A plurality of integrally formed robust lamps 34, 36, 38, 40
each ramp 34, 36, 38, 40 has a surface 42 facing the terminal member, the surface 42 being sloped radially outwardly and
The height of the inclined ramps 34, 36, 38, 4 is increased in the outer circumferential direction of the ramps 34, 36, 38, 4.
0 and adjacent downwardly bent corners 46, 48,
50 and 52 cooperate with each other to connect the wire 18 or 2.
0 both inwardly toward the screw clamping member 22 and downwardly against the terminal member 12 while forcing the wire 18 or 20 in the lateral direction relative to the screw clamping member 22. and the ramps 34, 36, 38, 40 and the corners 46, 48, 50, 52 are gripped to prevent longitudinal movement of the wire relative to the washer member 30. and each angled ramp 34, 36, 38 and 40 has one of the angled ramps 34 or 36 engaged with a wire 18 or 20 to urge the wire inwardly. When the wire 18
or to limit the inward movement of 20 and prevent said wire 18 or 20 from overly engaging a threaded portion 26 on said screw clamping member 22. Wire clamp assembly. 2. The sloping side surfaces 45 of the lamp flare outwardly, so that near its inner end 43 the lamp substantially extends over its peripheral edge 47.
2. A terminal wire clamp assembly according to claim 1, wherein the terminal wire clamp assembly is narrower than the wire 18 or 20, thereby facilitating inward biasing of said wire 18 or 20. 3. At least a portion of the sloped surface 42 of each ramp 34, 36, 38, 40 is rounded to ensure positive engagement with the wire 18 or 20 without unduly cutting or damaging the wire. A terminal wire clamp assembly as claimed in claim 1 or 2, wherein the terminal wire clamp assembly is adapted to: